Panel 2

Panel 3

Beaver turns back around to see Steve standing next to a bizarre one-eyed octopus monster. The door is open, which implies that Steve let the monster out, ignoring the warnings against doing so.
Beaver: "I probably should have forseen this..."

Panel 4

Panel 5

Close up of Qual'n'Gurtha
Qual'n'Gurtha: "Prepare to witness the end of your entire pitiful universe..."
Qual'n'Gurtha: "My hunger for it's destruction has never been hungrier!"

Fun Facts

Beaver is right - that is indeed not Elvis Presley riding the flying pig, but Buddy Holly instead. What a cunningly treacherous distraction trick by that pesky Steve!

This is in fact quite possibly a reference to an episode of Quantum Leap, where the main character, Sam, met Buddy Holly in a farm. Holly had written a song about a pig on the farm named Sue, which he called (naturally) "Piggy Sue", until Sam suggested he change it to "Peggy Sue".

Qual'n'gurtha is quite possibly a reference to Shuma-Gorath of Marvel fame. The "Lord of Chaos, Master of the Old Ones, Ruler of a hundred dimensions" possesses, aside from a desire to destroy the world, the exact body and appearance of Qual'n'gurtha; they share the single eye, green colour, and both have numerous tentacular appendages. Some speculation suggests that Qual'n'gurtha is no more than Shuma-Gorath's younger and less-powerful brother who nobody has ever heard about. Now we know why.